1 /* 2 * i.MX27 Power Management Routines 3 * 4 * Based on Freescale's BSP 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License. 8 */ 9 10 #include <linux/of_address.h> 11 #include <linux/kernel.h> 12 #include <linux/suspend.h> 13 #include <linux/io.h> 14 15 #include "common.h" 16 #include "hardware.h" 17 18 static int mx27_suspend_enter(suspend_state_t state) 19 { 20 void __iomem *ccm_base; 21 struct device_node *np; 22 u32 cscr; 23 24 np = of_find_compatible_node(NULL, NULL, "fsl,imx27-ccm"); 25 ccm_base = of_iomap(np, 0); 26 BUG_ON(!ccm_base); 27 28 switch (state) { 29 case PM_SUSPEND_MEM: 30 /* Clear MPEN and SPEN to disable MPLL/SPLL */ 31 cscr = imx_readl(ccm_base); 32 cscr &= 0xFFFFFFFC; 33 imx_writel(cscr, ccm_base); 34 /* Executes WFI */ 35 cpu_do_idle(); 36 break; 37 38 default: 39 return -EINVAL; 40 } 41 return 0; 42 } 43 44 static const struct platform_suspend_ops mx27_suspend_ops = { 45 .enter = mx27_suspend_enter, 46 .valid = suspend_valid_only_mem, 47 }; 48 49 void __init imx27_pm_init(void) 50 { 51 suspend_set_ops(&mx27_suspend_ops); 52 } 53